The purpose of this proposed pilot trial, Transitioning to Adult Care (TRANSIT), is to develop and test an intervention (i.e., a standardized, tailored transition program focused on enhancing adherence) to improve outcomes for emerging adults who underwent heart transplantation as children and transition to adult care. During the last decade, both pediatric heart transplant volume and survival rates have slowly increased. With better survival, more pediatric heart transplant recipients are entering young adulthood and transitioning to adult care. Transition to adult care typically occurs during late adolescence and early adulthood, a time of vulnerability, characterized by poor judgment and decision-making, risk-taking behaviors, and emotional reactivity. The term emerging adulthood has been used for this period between the ages of 18-25, recognizing that maturation is still occurring and many milestones still need to be achieved. Alarmingly, the literature has demonstrated that these emerging adults have not received the services necessary to successfully transition from pediatric to adult care facilities. Solid organ transplant emerging adults who have transferred care from pediatric to adult centers have experienced poor outcomes related to decreased adherence to the medical regimen, leading to unanticipated graft loss. Given the paucity of transition-related care and the risk for poor post transplant outcomes after transition from pediatric to adult care, research on best practices and outcomes analysis is needed. The aims of this proposed study are to (1) assess the feasibility (transition program adherence for those randomized to the intervention and survey completion for all participants) of TRANSIT, a 3 month long intervention, focusing on increasing heart transplant knowledge, self-management and self advocacy skills, and enhancing social support; and (2) determine the efficacy of TRANSIT on patient-level outcomes (i.e., variability of immunosuppressant blood levels and levels within target range, self-report of adherence to the medical regimen, and episodes of treated acute rejection) and use of health care resources. We will use the Treatment Adherence Impact model for understanding the impact of our adherence enhancing intervention on outcomes. Our intervention will use computer-based education modules with associated self-tests followed by face-to-face discussion and serial telephone follow-up by transplant coordinators. These data will inform development of an expanded multi-site randomized controlled trial. Our intervention may provide a model of transitional care for other populations of emerging adults (e.g., patients with congenital heart disease and transplantation of other solid organs).